Electrical connector



Jan. 2, 1962 M. F. O'KEEFE ETAL ELECTRICAL CONNECTOR Filed Jan. 21, 1960 Filed Jan. 21, 1960, Ser. No. 3,841 I (liairn. (Cl. 174S4) In the art of joining electrical connectors by crimping them together, it is paramount that the joint possesses good electrical conductivity and a high tensile strength. In connections involving communication wires (telephones, etc.), it is common to use a steel wire coated with copper. It is an object of this invention to provide a connection for such wire wherein the connector bites through the copper coating on the wire and forms a steelto-steel connection. This provides the high tensile strength required. Additionally, a copper ferrule in the connector is crimped onto the copper coating on the wire, so that a copper-to-copper connection is formed assuring good electrical conductivity.

Other objects and attainments of the present invention will become apparent to those skilled in the art upon a reading of the following detailed description when taken in conjunction with the drawings in which. there is shown and described an illustrative embodiment of the invention; it is to be understood, however, that this embodiment is not intended to be exhaustive nor limiting of the invention but is given for purposes of illustration in order that others skilled in the art may fully understand the invention and the principles thereof and the manner of applying it in practical use so that they may modify it in various forms, each as may be best suited to the conditions of a particular use.

In the drawings: I

FIGURE 1 is an exploded perspective View of a connector embodying the principles of this invention;

FIGURE 2 is a view similar to FIGURE 1 showing the connector in assembled relation;

FIGURE 3 is a view similar to FIGURE 2 illustrating the connector crimped onto a conductor;

FIGURE 4 is a sectional plan View taken along plane 4-4 of FIGURE 3;

FIGURE 5 is a sectional view taken through plane 5-5 of FIGURE 3;

FIGURE 6 is a sectional view taken through 6,-6 of FIGURE 1, including the insert.

As shown in FIGURE 1, the connector comprises .a number of parts, including an inner pair of metal ferrules 1i) and 12 which are connected together by a strap'l l. The portion between the ferrules permits visibility so that the operator can discover whether or not the wires are properly inserted therein. These ferrules fit centrally within a plastic sleeve 16. This sleeve is of a type perplane mitting the use of a crimping die thereon to crimp the ferrule without rupturing the sleeve. A flat, hard-metal plate 18, e.g. steel, with serrations or teeth on one side is adapted to be inserted in the ferrules. The ferrules are slightly oval, as shown in FIGURE 6, to accommodate this insert and permit it to dig into the sides of the ferrule. This relationship firmly retains the insert 18 within the ferrules It} and 12. A pair of rings 26 and 22 are designed to slip over the outside of the plastic sleeve at each end and crimp the plastic onto the insulation surrounding the conductors whereby a waterproof seal is formed. The conductor, as shown in FIGURE 2, has a central element capable of carrying electricity and an outside covering of insulation 26. As shown in 'FiGUlE 4, the conductive element has a central steel core 23 and an outer coating of copper lid. in assembly, the insulation is stripped away from one end of the conductor so that it may be inserted into the connector and to make the connection.

The connector is first assembled, as shown in FIG- URE 2, with the insert 1% within the ferrules lit and i2, and ferrules located centrally of the plastic'sleeve is having the rings 2t? and 22 on either end. The conductors 2 4 are prepared by stripping a length of insulation from the ends to be connected. Each of these conductors is inserted in one end of the assembled connector (FIGURE 4) so that they abut centrally of the ferrules. A pair of crimping dies (not shown) are brought to bear upon the ferrules so that the ferrules and insert are compressed onto their respective conductors, as shown in FIGURE 5. The action is such that the serrations on the inner surface of the insert bite through the copper coating on the wire and provide a steel-tosteel contact between the connection and the wire. The insert 18 is also slightly deformed so that there is a residual spring-back pressure tending to hold the conductor within the connector. Additionally, the compression of the ferrule onto the wire causes a good electrical connection between theferrule and the copper coating on the wire. The rings 2d and 22 are then deformed onto the plastic sleeve and the insulation 26 on the conductor to seal the connection against the intrusion of moisture.

It is apparent that a high tensile connection having good electrical conductivity is accomplished between apair of steel wires which are copper coated.

Changes in construction will occur to those skilled in the art and various apparently different modifications and embodiments may be made without departing from the scope of the invention. The matter set forth in the foregoing description and accompanying drawings is offered by way of illustration only. The actual scope of the invention is intended to be defined in the following claim when viewed in its proper perspective against the prior art.

We claim:

A connection between a pair of steel, copper-coated wires including: a pair of metal ferrules crimped onto said wires, a strap connecting said ferrules, a steel insert located in said ferrules, said insert comprising a rectangular metal strip having a smooth outer surface and serrations on its inner surface, said serrations implanted through the copper coating of the wires into the steel, said insert being deformed into an arcuate shape to pro vide residual pressure, the edges of said insert biting into the ferrules, an outer plastic sleei e surrounding the ferrules, and a pair of ring members, one on each end of the plasticsl'eeve connecting the plastic sleeve to the insulation on the wire.

References Cited in the tile of this patent UNITED STATES PATENTS 2,247,928 Temple July 1, 1941 2,268,617 Pierce Jan. 6, 1942 2,478,{)82 Broske Aug. 2, 1949 2,774,810 Ritter Dec. 18, 1956 

1. A CONNECTION BETWEEN A PAIR OF STEEL, COPPER-COATED WIRES INCLUDING: A PAIR OF METAL FERRULES CRIMPLED INTO SAID WIRES, A STRAP CONNECTING SAID D FERRULES, A STEEL INSERT LOCATED IN SAID FERRULES, SAID INSERT COMPRISING A RECTANGULAR METAL STRIP HAVING A SMOOTH OUTER SURFACE AND SERRATIONS ON ITS INNER SURFACE,SAID SERRATIONS IMPLANTED THROUGH THE COPPER COATING OF THE WIRES INTO THE STEEL, SAID INSERT BEING DEFORMED INTO AN ARCUATE, SHAPE TO PROVIDE RESIDUAL PRESSURE, THE EDGES OF SAID INSERT BITING INTO THE FERRULES, AN OUTER PLASTIC SLEEVE SURROUNDING THE FERRULES, AND A PAIR OF RING MEMBERS, ONE ON EACH END OF THE PLASTIC SLEEVE CONNECTING THE PLASTIC SLEEVE TO THE INSULTATION ON THE WIRE. 